Privacy-Preserving Data Sharing via PCA-Based Dimensionality Reduction in Non-IID Environments

The proliferation of mobile devices has generated exponential data growth, driving efforts to extract value. However, mobile data often presents non-independent and identically distributed (non-IID) challenges owing to varying device, environmental, and user factors. While data sharing can mitigate non-IID issues, direct raw data transmission poses significant security risks like privacy breaches and man-in-the-middle attacks. This paper proposes a secure data-sharing mechanism using principal component analysis (PCA). Each node independently builds a local PCA model to reduce data dimensionality before sharing. Receiving nodes then recover data using a similarly constructed local PCA model. Sharing only dimensionally reduced data instead of raw data enhances transmission privacy. The method’s effectiveness was evaluated from both legitimate user and attacker perspectives. Experimental results demonstrated stable accuracy for legitimate users post-sharing, while attacker accuracy significantly dropped. The optimal number of principal components was also experimentally determined. Under optimal configuration, the proposed method achieves up to 42 times greater memory efficiency and superior privacy metrics compared with conventional approaches, demonstrating its advantages.